Multiple unit power lawn mower



oct, 27,1942. l R. w. $95.559 l 2,299,859

MULTIPLE UNIT POWER LAWN MOWER Filed Sept. 3. 1940' 6 Sheets-Sheet 41 9 INVENTOR RALPH WJ'PE/JE/a .l BYWM, Ml* )um ATTORNEY Oct. 27, f1942. R. w. sPElsER MULTIPLE UNIT POWER LAWN MOWER Filed Sept. 3, 1940, 6 Sheets-Sheet 2 Oct. 27, 1942. R., w. sPElsER MULTIPLE UNIT POWER LAWN MOW ER1 Filed Sept. 3. 1940 Oct. 27 1942.

R. W. SPEISER MULTIPLE UNIT' PQWER LAWN MowER Filed sept. 3. 1940V 6 Sheets-Sheet 4 INVENTOR RALPH WSPE/SEE ATTORNEY l 0t- 27, 1942-K 1R. w. sFElsl-:RI

MULTIPLE UNIT POWER LAWN MOWER Filed sept. s. 1940' 6 sheets-sheet 5 QON NOM QM" mom WOM H W m M W., Y.

mi L nf ct. 27, 1942. v

R. w. sPEls'ER MULTIPLE UNIT POWER LAWN MOWER Filed sept. s; v1940 6" Shets-Sheet 6 Mad .v5 `P1. R5. n www mn m mm. mi MW B Patented l'Oei'. 27, i942 y UNITED vSTATES PATENToFFicE- i MULTIPLE UNIT POWER LAWN MOWER Ralph W. Speiser, Minneapolis, Minn., assigner to Toro Manufacturing Corporation of Minne-` sota, Minneapolis', Minn., a corporation of Minnesota Application September 3, `1940, vSerial No. 355;171

24 claims. (01.56-7) l Y This invention relates to an improved multiple mowing unit traction mowing machine, and more particularly to a machine in which the mowing units are grouped in overlapping relationship about a small 4and compact traction vehicle, and

the mowing elements of each'unit operated from the power source on the-traction vehicle.

It isan object of theiinvention to provide a mowing machine having a relatively small main supporting frame, which has a. width of only `a small fraction of the total width of the swath cut.

It is a further object of the invention to'provide in such a mowing machine, provision for carrying the operator of the machine and to provide .an articulated frame whereby the weight of the operator may be shifted to steer the machine.

It is another object of the invention to provide for reverse drive ofthetraction unit so that the entire unit maybe backed out of restricted spaces. Y f- It is a further object of the invention to provide prevented, when mowing in or the like.

Other and further objects oi the invention are cemeteries, parks,

those inherentin thefstructure illustrated, de.I scribed and claimed herein.

` showing the control and power drive mechanism.

a machine in which the mowing units are pivctally carried by the main traction frame with a large Vproportion ofthe Weight of the unit transferred to the frame.

It is also an object of the invention to provide articulatedV connections between the mowing units and frame combined with means transferring 'a large proportion of unit weight to the frame, in such manner that play in the articulated connections does not sacrifice flexibility.

It is another and a particular object of the in- Figure 6 is a top view of the machine with the' control and power drive mechanism removed.

Figure 7 is an isometric view showing the sub'- i'rame linkage with, and position with respect to,

the main frame.

vention to provide a mowing machine in which thernowing units may operate with full power throughout very "wide anglesv with respect to the position oi the main propelling frame, and to provide in such a structure a novel power transmission system between the mowing units and the frame whereby adequate power is always available at the cutting reels.

It is another object of Vthe invention to pro-f vide for a substantially constant transfer of Y mower unit weight to the main-frame regardless movements in a transverse plane, and adapted for the connection thereto of a multiplicity of mowing units,y by pivotal means extending in the direction of travel. y

Finally, it is an object of the invention to provide bumper surfaces positioned on the mowing unit so that injury to momunents, trees, etc., is

Figure 8 is an isometric view of a portion of a wing mowing unit which illustrates its manner of pivotal attachment to the sub-frame.

Figure 9 isan isometric view of the sub-frame which illustrates the wing mowing unit pulley position with respect to its cooperating sub-frame drive pulley and also the latching means for locking the wing mowers in pivoted relation with the sub-frame.

Figure 10 is a rear view of the 'machine as viewed along the lines I0-i0 ofFigure 2, parts being removed and parts left out.

Figure 11 is a rear view of the machine as viewed` along the lines Ii-II of Figure 2.' parts being removed and parts left out.v

Figure 12 is a plan view of an alternate construction for the undercarriage'of the trailing unit 35.

Figure 13 is' a right elevation of the trailing unit construction shown in Figure 12.

Figure 14. is an isometric view with'sorneA of the parts removed and others broken awayshowving `one of the cutting unitsy of the assembly.

Figures 15a and 15b are fragmentary views in section of the two bearing units of the reel shaft.

Throughout the drawings. identical parts are indicated by the The tractorframe and steering structure same numerals.

driving wheels II5I2 and I3-I4, and a trailing set of tandem wheels I6 and I1. The main frame structure is best illustrated in Figure '1. The frame consists of aforward cross-piece 20, which is preferably integrally formed with rearwardly extending side pieces 2I and 22. The side pieces 2I and 22 are joined together by a central transverse frame member 24, which is preferably of tubular cross section welded to the side pieces 2| and 22. At the middle of the central ,transverse frame 24, there is an upwardly extending gusset plate 25, which is strongly braced by means of angle pieces 26 and 21. (see Figures 5 and '1), and extending rearwardly from gusset plate 25, there is a central frame member 28, which is likewise preferably of tubular cross section. At the rear end of the central framemember 28, there is formed a vertical pivot post 30 which serves as a coupling for the trailing unit, generally designated 35. Y

The trailing unit 35 consists of a central frame 36 having a forward upwardly extending pivot pin 31, which is received in the pivot post 30 (see Figures 1 and 2). The pivot pin 31 is provided with a cap 38 which is held in place by a through pin 39, of small diameter. Accordingly, the trail--v ing unit 35, as a whole, is permitted to pivot with respect to the main frame Ill.

The trailing unit 35 is provided with an axle 4 9 on which are mounted wheels I6 -and I1 previously mentioned. In the alternate construction i (Figures 12 and 13) axle 40'is engaged by longitudinal pivot 4I for vertical oscillation in a transverse plane. Extending above the frame 36 of the trailing unltfthere is a driver seat 45, which 1liA seat unit being mounted upon the frame 36 by,

through bolts 49.

member 28, there is a xed s teering'column 52, upon which rearwardly extending handle bars 53 aremounted equipped with handle grips 54. The whole handle bar unit is adjustably coupled to the xed steering column 52 by means of the clamp l56 so that the position of the handle bars may be adjusted for height. Extending downwardly from the central frame member 28 are a pair of foot rests 58, which may, if desired, be adiustably mounted.

Steering of the unit 35 with respect to the frame I0 is accomplishedby the reaction upon seat portion of the trailer unit 35 when the operator exerts pressure upon the handle bars 53 and foot rest 58 on the main frame member I9 to swing the unit 35 about pivot post 39. Hence, as the vehicle proceeds, steering is accomplished by the `operator swinging the seat 45 and unit 35 to the right or to the left. Since the operators seat' 45 is farther away from the pivot post 30 than wheelsIG, reactive steering force of the operator upon seat 45 is to some extent multiplied and easy steering is accomplished. Hence, it is possible easily to achieve the4 extreme steering positions, one of which positions is shown in Figure 6.

In this position, the overlapping relation of the swaths cut by mowing units A, B and C is indicated by the dotted curved lines. 'I'he amount of overlap of the swaths is equal for straight forward mowing andis made sufficient so that there will always be overlap evenl on curves.

Power source and power transmission 20 of the frame, and the rear engine bracket 62,

which is centrally mounted on the central transverse frame member 24. Frame member 24 likewise carries a pair of vertical posts 64 and 65, upon which the gasoline tank 68 and ltool hatch 69 of the engine are mounted. Vertical posts 64 and 65 are the previously named angle bracket pieces 26 and 21, in fact, they are bent of one piece of angle iron forming a U-member.

The drive shaft of the engine is at the righthand side of the unit, as shown in Figures 1 and 5, the drive shaft being indicated at 10. Upon the drive shaft, there is mounted a reverse gear, generally designated 1 I, of any conventional type, the driven or output side of the gearing being the chain sprocket 13.

The reversing mechanism illustrated has forward, neutral and reverse conditions of operation, which may be selectively attained by means of the gear shifting lever 15, connected by means of link 16, bell crank plate 11, link 18, to the shifting lever 19, the latter being mounted conveniently with reference to the operator station, for pivotal forward and reverse movement on the left side of the fixed steering column 52. The shifting mechanism is best illustrated in Figures 5 and 11.

The forward and reverse transmission herein illustrated, comprises'a drum member 89, upon the outer surface of which there is mounted a brake band 82 controlled by the link 83 lcoupled to the side arm 84 of lever 15. face of the drum member 80, there is provided a v splined surface 85 in which a. pluralityof Adriven clutch plates are arranged to operate,'these being -in cooperatingl relation with other clutch plates splined in the drive shaft. The clutch plates are shifted from disengaging to engaging position by means of the thrust bearing 81 operated by under lever 89, the latter, as well as lever 15, being pivoted upon bolt A9I. The two levers 89 and 15 are resiliently coupled together for slight relative movement under stress, by a pair of upwardly extending lugs 93 and spring 94.

Studs 328 are circumferentially spaced about the power take-01T shaft (not shown) of the engine 6I! and secured for rotation therewith. Rollers 32| slidably mounted on the studs 320 vare also journaled in apertures circumferentially Drive shaft 10 extends from a coupling with the engine 6U through the entire planetary gearing 95, and brake-clutch unit 1I through a side frame member 91, where itis journaled, and always revolves in a clockwise direction as viewed in Figure 2. .When the shift lever 19 is moved On the inner sur ling 85.-

. i '2,299,859 forwora1y.it servos through tho nnss 1s and 1s.'

and the lever 15, to disengage the brake band 8,2 and to l,engage the clutch members 80. results in the shaft 10 driving the drum 80, which in turn revolves'the casing of the planetary gear- Within the planetary gear housing, `there is a pinion gear 98 keyed to the shaft 10, this gear being revolved with the shaft at all times. Since gear 98 isrevolved with the shaft and the housing of the planetary gearing 95 is likewise reserves to disengage the drivingconnection between the clutch discs 86 and the drum 80' and serves to tighten the brake band 82 upon the outer surface of the drum, the spring 94 insuring that both brake and clutch are completely operated. When this occurs, power is transmitted to the sprocket 13 in a reversevdirection as follows:

j Shaft 10 rotates pinion gear 98. Since the housing of planetary gearing 95 is now stationary due to the holding action of brake 82,` the planet gears revolve upon their stub shafts and serve to rotate the pinion gear |02 in a reverse direction. Y

' When the lever 19 is moved to an intermediate position, both theclutch members 86 and the brake member 82 are disengaged. When this occurs, the drum member 80 and the housing of planetaryy gearing 95 revolve at half speed as compared to the engine speed and does not trans-4 mit power either inthe forward or the reverse direction.

Immediately below the chain sprocket 13, there vis positioned a differential, generally designated |05, having a large outer chain sprocket |01. The internal construction ofthe differential |05 is generally similar to that used in automotive construction, although somewhat smaller, and is mounted upon and drives dual wheels |||2 and |3-|4, which are` mounted on axle |09. The outer ends. of axle |09 are carried upon downwardly extending gusset plates ||2 and ||3, best illustrated in Figure 7.

Accordingly, the engine 60 mayl be used to propel the vehiclein either the forward or rearward direction, or the vehicle can be caused to remain immovable, by suitable manipulation of the control lever 19.` i

The main drive shaft 10 extends outwardly beyond the 4right-'hand side of the frame members This 91 as shown in Figure 5, and upon the outer end there is mounted a clutch unit, generally designated H5, having an outer chain drive sprocket |I1. The clutch member ||5 is of any desired type and is controlled by a lever ||9 pivoted to the frame member '91 at bolt |20. The lever` The shaft, |46, also carries slinger cups |49dv .thereby shifting the clutch ||5 to the power transmitting position. The vpower take-oi! sprocket H1 serves to-drive the'revolving reels of the cutting units by*I means "which will be described hereinafter.

Upon tho right-hand hahdie har sa. there is mounted a speed control lever |3l, which is connected by a wire |33 to the engine 60. Itis, therefore, possible for the operator, when seated at 45, to not only control the forward and' rearward motion o f the mower. but also to control the speed of operation and'to control the rotation of the cutting reels of the mower units.

Mowng unit A About the main drive vehicle. there are positionedthree (3) moving units, generally designated A, B and C-as shown in Figure 1. The mowing units `are of generally similar construetion except so far as the power driveconnec tions are concerned, units B and C being an enantiomorphic pair, otherwise identical.

Each of the 'mowing units consist of `side frame plates |40; which are connected together by two or more intermediate frame members |43, and by the bed knife |44. The frame members, |43, are preferably of tube steel welded to the side plates The knife bar |44 is preferably made of steel plate, grooved and bent along the groove so as to close the groove and form aV-shaped bar. The knife bar may if desired be an'integral rolled steel bar of the shape shown, ratherthan the folded bar illustrated'. At the ends of the bar there are welded gusset plates, |44a, to which in turn there are welded outwardly4 extending plates, |44b, one at each end of the knife bar. Upon the unit side plates there are welded outwardly extending brackets' |40b, which overlie plates |44b when the knife bar is assembled on the unit. The under sides of brackets |40b and the upper sides of plates |44b are milled with a circular cutter, and a circular disc key I44cis inserted and the whole 'held in place by adjusting screws |44d which pass thru brackets l40b and are threaded into plates |44b`. The axis of pivoting of the bar is the centre of disc keys |440. The keys, in additionI serve positively to prevent endwise movement of bearings upon'which 'the reel revolves, are detachable as an assembly from the cutting unit frame, this being illustrated in Figures 14, 15a and 15b. Each end of the reel shaft |45 projects through a bearing housing |48. hasl an apertured flange |48a thru which cap screws |48b kpass for fastening the housings to j the unit frame. The housings |48 are bored to receive ball bearingunits l48e and oil seals |48c.

which embrace each side of the housing. The slinger cups serve to exclude tough grass and wire from the oil seals |48c, thus enabling them tol wear longer and function bett r.

The entire assembly of slinger cups |48d, oil seals |48`c. and bearings I 48h are held assembled in the housings |48 by-means of nuts |46a at 'rho reel of the cutting unit, together with the The housing |48 each end of the shaft, and the exposed ends of the shaft |46 are provided with cone centers |46c, so that` the reel may be set up accurately in a grinding machine for sharpening, all without dismantling the bearing units.

Referrirignow` to the forwarding mowing unit A: The unit A is carried with respect to the traction vehicle by means of an upper U-shapedl frame member |50 and a pair of lower side links |5| and |52. The U-shaped frame member |50 has its rearwardly extending spaced arms |53and |54 coupled to the main frame side pieces 2| and 22 by means of pivot bolts |51 and |58. The front portion of the U-shaped frame member |50 may accordingly move forward and downward about an arcuate path, the center of which is formed by pivot bolts |51 and I 58. Upon the front center part of the'frame member |50, there is mounted the ball portion |60 of a ball and socket coupling, generally designated |6|, the coupling |6| being in turn mounted upon the center part of the front mowing unit A. h I

The rearr end of the right-hand lower side link |5| is coupled to the gusset plate I2 of the main frame by means of a ball and socket joint |63, the ball portion of which is yshown at |64 in Figure 7. The front end of the lower side link |5| is coupled by a similar ball and socket joint |65 to the lower rear portion'of mowing unit A. The left-hand lower side link member |52 is likewise coupled to the gusset plate v| |3, and to the mowing unit A by means of ball and socket joints |61.

Since the U-shaped frame |50 is pivoted to the frame at |51,and |58, it is preventedfrom moving sideways. Hence, the ball |60 of joint|6| servesto prevent the mower unit A from. shifting laterally, although the unit A may tilt freely l neutral positions of Figure 2, the mower unit A I is tipped upwardly a slight amount at the front. this being illustrated inl Figure 4. The upward tipping function is desirable so as to prevent the front end of the unit A from digging into the surface 0f the turf when mowing undulating surfaces.

A portion ofthe weight .of the mowing unit A is carried by a roller |68 on the rear part of unit A, but the major portion of the weightY is carried by means of a link chain |10 extending from `the hook `|12 on unit A upwardly over pulley wheel |13, and then backwardly into a rod |14, which extends intothe tubular housing |15 mounted upon the 'gusset plate |16, thev latter being in` turn mounted upon the central frame member 28. The front part of the tubular housing |15 is closed except for a small hole through' which ythe rod` |14 passes, and the rod is provided with a rear collar |18. Between the collar '|18 and the front end of housing |15, there is compressed a ,spring |80, which serves to carry'about 85% of the weight of the mowing unit A, this being variable byadjusting the compression 4of spring |80. It is vdesirable thus to transfer the weight of the mowing units to the main chassis as the traction of th'e latter is thereby increased. The proportion of the mower unit ally designated 236.

cient to maintain ground contact, this weight being insufficient tcl damage the turf during sliding of the unit on curves.

In order to elevate the mowing unit A during transporting conditions, there is provided link.

chain |82 extending from the rear end of rod |14 and thence to an adjustmentmember |83 pivoted to the lift lever |85., The lift lever is coupled at pivot bolt |81 to the fixed plate |88 on stationary steering column 52. In Figures 2 and 4, the lever 85 is shown in full lines in the down position, under which conditions the rear link chain portion |82 is slack and the weight of the mower unit A is in part carried by the spring |80. `When the lever |85 is rotated upwardly to the dotted line position shown in Figure 4, the link chain |82 istensioned over xed pulley |90, which is likewise pivoted upon the bracket 9| attached to the fixed steering column 52, and when thus tensioned, chain |82 takes the weight of mower unit A and relieves spring |80. When the lever |85 is in the dotted line position of Figure 4, it is over-center with respect to the mounting pivot |81, and accordingly is self-holding in the elevated position.

Mowing units B and C The lateral mowing units B and C are not cou- Ipled directly .to the traction transport vehicle, but are instead carried by a sub-frame member, generally designated 200, the details of which are best illustrated in Figure 9. The sub-frame member 200 consists of a front tubular bar 20| having upright pieces 202 and 203 welded thereon, at the upper ends of which, there are welded rearwardly extending side pieces 204 and 206, being preferably made of square steel tubing.

An intermediate framev piece 208', preferably of round tubing, iswelded to the rearwardly extending side pieces 204 and 206 and vserves to stilen the unit. Upon the front upper portion of the side pieces 204 and 206, there is welded a tube 2|0, which not only serves as a frame member, but also serves as a means for supporting a pair of journals 2|2, one in each end of the tube 2|0, in which the shaft 2|4 is rotatably mounted. The shaft 2|4 carries a pair of V-type pulleys 2|^6 and 2|1 and at one end carries a. chain sprocket shown in the dotted lines at '2|9 in Figure 9. The sprocket 2 I8 is Ipositioned so as to be in alignment with the chain drive sprocket ||1.

At the outer ends of the front tubular bar 20|, there are spherical heads 220 and 222 of ball and socket joints 224 and 226 respectively, the ball and socket joints 224 and 226 being carried upon the rear ends respectively of the lower rear side links `228 `and 230, the front ends of these links being coupled by similar ball and socket joints 23| and 232 to the gusset plates ||2 and ||3 of the main tractor frame.

To the center part of the intermediate frame piece 208 of sub-frame 200, there is coupled a ball and socket joint 234, which serves to receive the spherical head portion of a vball and socket coupling forming the center of a Y-frame, generl The forwardly extended spaced legs 231 and 238 of the Y-frame 236 are coupled to the main tractor frame by means of ball and socket joints 239 and 240, which are.

joined to the upwardly extending brackets 242 and `243, these latter being'welded to the central frame member 200'is mounted in -a manner simweight carried by roller |68 is made lust sulll- 75 ilar to that used in vmounting the front mower unit A in that thereA is an upper central connection` to the sub-frame member 288 at the ball and socket Joint 234 and a pair of lower rear side links 228 and 238. `The ball and socket Joints :as and m, .by which the bifurcated ends of the Y-frame 238- are Joined to the main chassis, serve to prevent the frame from shifting laterally with respect to the chassis. Hence, ball T and socket Joint 234 on the Y-i'rame 236 serves to prevent' lateral shifting of the sub-frame 288, although the sub-frame mayv tip 'freely about a longitudinal axis through the ball joint. The tippingl of sub-frame 288 and mower units B and C attached thereto, about an axis transversely of the main chassis, is determined by the effective pivotal length oi' the Y-frame :236 and the side links 228 and 238, the effective length of the Y-frarne 236 beingsomewhat longer than the effective length of the lower side links 228 and 238. `As a result',v the front portion vof the subframe member 200 is tipped upwardly as the subframemoves above and below the neutral plane shown in Figure 2, the movement above the neutral plane being illustrated in` Figure 4. This tipping action is transmitted directly to mower units B and C, whichare mounted on the subl frame'288.V

-Upon the rearwardly extended side piece 284 oi' the sub-frame.r 288, there aremounted pivot blocks 244 and 246, and upon sidepiece 286, there are mounted similar pivot blocks 248 and 258. Each ofthe pivot blocks is apertured along a rearwardly extending axis illustrated, for example, by the axis D-Dofl Figure 9. The aper-` tures in -pivot blocks 248and 258 serve to receive pivot pins 252 and 253 respectively mounted on the inner side plate |4| of mower unit B (see f Figure 8). 'I'he pivot pin 252 is merely a round "slide into the grooves 254 and 255 respectively -thus retaining the pin 253 in pla-ce in the aperture. This serves to prevent displacement of the` mower unit Bwith respect to the sub-frame 200.

Locking clip 260 is pivoted to the sub-frame by means of `arm 263 and is held in locking position by means of a spring clip 265 which is likewise pivoted to the 4sub-frame and bolt 261, the spring clip-265 being swung over the locking clip 268 when fthe latter is in place as shown at 218 in Figure 9.- The mowing units B and C can ac' cordingly be removed from.' the sub-frame B merely by raising the clips 268 and 218.

`At the center part of the front tubular bar A` 28|, there is anreye 21| -to which there is coupled a supporting link wchainv212 (see Figures 2 and 10). The link chain 212 passes upwardly into the hollow stationary steering column 52, and is provided at its upper end with a rod portion 213 terminating in a washer at adjustment nut 214. 'I-he spring 215 surrounding the rod 213 is'compressed when chain212 is drawn downwardly by the weight of sub-frame 288 and mowing units B and C coupled thereto. In thismanner, any downward force on the sub-frame 288 is transferred to the main traction vehicle.

ythe tinck 25s .welded Extending upwardly from side pieces 284 and 286 of sub-fframe 288, there ,are brackets 216 and A218 having eyes 211 and 219 respectively thereon. I'he brackets 216 and 218 serveas. attachment points for vreceiving tensionsprings 288 and 282, the outer ends of these springs being attached respectively to the center eyes 283 and 284 or mowing unit cross frame members |43. Accordingly, a proportion of the weight of each mowing unit B and C is transferred to the subframe v288 and from the sub-frame 288 to the traction vehicle by virtue of the link chain 212.

The length and attachment positions of springs 288 and 282 is such that the lifting torque on the mowing units B and C will b e substantially equal to the downward torque caused by the weight of the units about their'pivot axes; for'it will be observed that the torque arm shortens `and the vdownward torque caused by the weight 4ofthe unit accordingly decreases as the mowing unit inclines downwardly. This is illustrated inFigure 10 for mowing unit C, which isshown as resting on a downward slope. At the same time, the torque arm of spring 288 iny respect to the pivot axis E is lessened asthe mowing unit inclines downwardly, thereby substantially balancing the unit in all inclined positions. As the spring ten" sion increases,` the torque arm decreases, and vice versa. f

In Figure 10, the mower C, being positioned on a downward incline, its supporting spring 288 is greatly` tensioned. The spring 282 of mower B,

which rests on'an upward slope, is tensioned to a muchl lesser degree. However, a line passingthrough pivot axis D of mower C and perpendicular to the tensional force of spring 288 (torque arm) is shorter than a corresponding line through pivot axis D of mower B and perpendicular to the tensional force of spring 282.

In fact, the torque which isthe product of the `unit length of the line and the force is equal in both cases, and is equal Whatever be the position of mowers B and C with respect to each other to the sub-frame.

'I'he proportion of the weight of units and C,

carried by the ground rollers of the units, is as in the case of unit A, just sufiicient to maintain ground contact. This Weight does not unduly depress the turf nor damage the turf during sliding on turns. l

The power drive forV the mowing units The front-mowing unit A is provided with a reel shaft 286 extending at the-right-hand side of the unit as shown in'Figure 1 upon which shaft, there is mounted a chain sprocket wheel 281. As shown in Figure 15b, the sprocket 281 is rotatably mounted on hub 281a which is keyed to the reel shaft |46 of unit A. Upon the end of the reel shaft there is threaded a clutch disc 281b. Between the sprocket 281 and clutch disc 2811;, and also between the sprocket and the face of hub '28111V there are positioned friction discs 281d. The disc 28111 is drawn up so as to produce the desired clutch friction and is locked in place by nut |4611 on the end of the reel shaft. Ordinism from excessive strains.

narily sprocket drives the shaft |46 without slip.-

ping but should the reel becomes jammed by striking a stone or iron, or the like, the sprocket will slip, thus sparing the transmission mecha- Sprocket wheel 281 of unit A is positioned so as to be in alignment with the chain sprocket ||1 (see Figures 1 and 5). Likewise, theA chain' sprocket wheel 2|! on shaft 2|4 of sub-frame detriment in view of the length of chain between.

the various sprockets and the inherent ability of the chain to operate satisfactorily in slight misalignment. In addition, the mainframe of the machine is provided with an idler sprocket A2,299,859 n A 'described above, superior results are obtained under a wide range cutting condition.

The cutting reel of unit A iS Adriven directly by the chain 292, but units B and C are indirectly driven from the intermediate shaft 2M on subframe 200 by means of V-belts 299 and 300, which 289 mounted so as to be drawn rearwardly by i means of spring 290. Over the driving sprocket ||1 and the driven sprockets 2|9 and 281, there is arranged a drive chain 292. Since the rotation is clockwise in the direction of arrow 293, as shown in Figure 2, the maximum tension'of the driving chain occurs in the portion 205 between sprockets H1 and 2|9 since this portion of the chain transmits the power for rotating the two rear units B and C and also that for rotating the forward unit A. If lit is assumed that the power consumed by all of the cutting reels is equal, the tension in the portion 295 of the chain may be illustrated by the vector 295' of Figure 3, vector 295 being substantially three times as great as the vector 296', which is respective of the tension in that portion of the chain between sprockets 2|9 and 281. The tension between sprocket 281 and idler 289 and between the idler 289 and the drive sprocket H1 is considered as negligible in view of the fact 'that no load is carried in these portions of the chain, tension being maintained only by the action of spring 290. In'the vector diagram of Figure 3, the direction of the vector 295' is laid out as parallel to the portion. 295 of the drive chain, while the vector 296' is laid out parallel to the portion 296 of the chain, Figures 2 and 3 being referable, one to the other.

The vector su'm of vectors 295' and 29B can accordingly be represented by the vector 298, which represents the total forward force to chain 295, upon the sub-frame 200 under normal level, evenly loaded, conditions. The position of the Y-frame 236 and the lower rear side links 228 and 230 is preferably made parallel to the vector 298 so that undernormal level running, evenly loaded, conditions in the mower, the driving tensions of the chain drive will not produce any lifting or lowering of the sub-frame 200 and mowing units B and C attached thereto. The fact that the portion 295 of the driving chain is nearly lequal in length to the average effective length of frame 23B and-side links 228--230 preserves the nearly parallel relation'between the resultant force 298 and frame and links 236-228 and' 230 throughout a wide variety of positions of the sub-frame above and below the neutral plane.

Likewise, it will be observed that the U-shaped frame |50 .and the lower right and left side links |5I and |52 are nearly -parallel to the portion 296 of the chain. Therefore, the driving force in the chain produces no substantial elevation or depression of the mowing unit A under normal vfects the position of the cutting units, but it has been found that byarranging the apparatus asl are arranged to operate over-i pulleys 2|6 and 2|1 respectively. f

Referring particularly to Figure 9, it will be noted that the pulley 30| of 'mowing unit B is shownl in the position maintained during normal level running conditions. The pitch'line of the uppermost part of pulley 30| of unit B andthe pitch line of the lower portion of pulley 2|'| are both tangent to the axis D-D, upon which mower unit B pivots up and down. The plane of pulley 30| is through axis D-D and when `the unit B pivots up and down, the plane of pulley 30| likewise pivots about axis D-D. The

tension side of the V-belt, arranged over pulleys 2|1 and 30|, is along the line T-T and accordingly, the Vbelt, on the tension side, always enters pulley 2|1 exactly in line with that pulley, regardless ofthe position in which pulley 30| may be disposed due tojupward or downward swinging movement of mower unit B. Likewise, the V-belt will enter the lower side of pulley 30|, exactly in line with that pulley regardless of the angular position of that pulley.

From another viewpoint, pulley'30l and the lower part of V-belt 300 below pulleys 2|1 and 30| may be considered as always in one plane,`

Precisely, lthe' same arrangement of pulley is provided for mower unit C and therefore power is transmitted constantly to mower units B and C regardless,of their inclination with respect 'to the sub-frame 200. It has been found that with this arrangement, it is possible to transmit full power to the mowing units B and C even when they are'displaced as much as 60 degrees vabove and below horizontal position, and that even under such extreme conditions of displacement,

suicient' power can betransmitted to stall the i gasoline driving engine 60, as may occur when exceptionally heavy growth is being cut.

As another feature of the V-belt drive between the sub-frame 200 and the mowing units B vand C, it is desired to be pointed out that the4 adjustment nuts 256 may be changed by varying the position of grooves 25l'and 255 with respect to the mowing unit frame members 258 and MI, vand by this means the tension of lthe V-belts may be adjusted. The tension is a.d` justed so that under normal' running conditions,

the V-belt runs relatively high up vin the groove.-

of the pulleys and due to this fact, when the revolving reel of either of the mowing units B and lC strikes hard obstructions such as a rock or nail, the belt will slip in the pulley. However, where the load is gradually increasedupon the cutting reel, as during encountering exceedingly tough growth, the V-belts will tend to pull deeper and deeper into the- V of the pulleys and as a result, `under such conditions, a. very much greater amount of torque can be transmitted than where the units are runningunder rela- In order to transport the mowing machine, the operator manipulates lever |85 on steering column 52 from the full line to the dotted line position shown in Figure 4 thereby elevating the front mowing unit A to the dotted line position.l Mowing units B and C are then swung upwardly to the vertical position shown. in Figure -l1, the V-belts preferably being removed during this extreme condition. Eachof the mowing units is provided with an upwardly and inwardly extending bracket arm 308, which is apertured as shown at 309. The fixed steering column 52 isy provided with a cross-bar 3|0 at its upper ends. the outer ends of which are turned down so as to provide an extending portion 3|I of smaller diameter at each side. Beneath the cross bar 3|0 and extending beyond either end thereof,r

there is a spring clip 3|2. When the mowing units B and C are in the vertical position shown in Figure 11, the apertures 309 move into position over the extending portions 3|| of the cross bar, 4and the spring clips 3|2 catch the innermost end of thearnis 308 and retain them againsty outside displacement. In this elevated condition, all of the weight of the mowing units B and C is carried in part by the cross bar 3| 0, and thence through the steering column 52 to the frame member 28, and in part -by the link chain 2|1 which serves to apply an upward force` on the .l

sub-frame 200 and hence upon the mowing units. It will be observed that in the position` shown in Figure 1l, the mowing units have an over-all width within the outside dimensions of the main traction vehicle, and the machine may accordingly be taken through very narrow gates.

When it is desired to remove either of the mowing units B and C.,it iscnly necessary to elevate the retaining clips 260 and 210 whereupon the units B and C` may be moved backwardly so as to disengage the pivot pins 202 and 253 from the pivot blocks 248 and 250 (for mowing unit B) or the corresponding parts for mowing unit C. In this way, either of the mowing units may be readily disassembled from the machine for repair and servicing.

All of' .the ball and socket joint connections, for example, t-hose en the U-frame member |50 and mowing unit A, and those by means of which links |5| and |52 of mowing unit A, and links lining serves to provide a relatively solid and yet resilient coupling at each of the joints.

Alongthe front and side portions of the mowl ing unit A and along the front and outer ends of mowing units B and C, there are provided spring bumpers 3|3, 3H and 3|5, which are preferably encased in rubber hose so'as to provide a soit and resilient cushion, which will serve t`o` prevent the mowing machine from chipping or otherwise damaging monuments, curbs, trees. etc.; against which it may accidently be driven.

Many obvious variations may be made in the apparatus herein described 'and illustrated, without departing from the spirit of the invention claimed.

What I claim is:

1. A power mowei` comprising a self-propelled wheel` supported frame, said frame being composed of a U-shaped member, a transverse member secured at its extremities to the open ends of said U-shaped member, a longitudinal midframe member extending rearwardly from Said transverse member, and a plurality of mower units .flexibly attached to the .frame for movement with the same along an undulating surface. u y

2. A power mower comprising a wheel supported frame, propelling means for the frame supported thereon, V,and a. plurality of mower units flexibly attached thereto, said frame being composed of a U-shaped plate member, a transverse tubular member secured at its extremities to the open ends of said U-shaped plate member, a longitudinal tubular Inemberv extending rearwardly from said transverse member and `secured at its forward end thereto in a position midway between the ends thereof.

3. A power mower'comprising a main frame having a U-shaped member, a transversemember connecting the open end of the U-shaped member, a longitudinal member secured to said transverse member at its midpoint and extending rearwardly therefrom,

two-wheel `support for the front part of said fra-me, a rear wheel support pvotallyattached to the frame at said rigid vertical pivot memb er, and an operator supporting means carried cn the rear Wheel support.

4. A power mower, comprising a main supportingr frame, a front mower unit, a pair of wing mower' units, said wing mowerunits being combined in overlapping arrangement with respect to the front mower so as to cut a swath of grass substantially Vthree times the Width of one unit, means pivotally connecting the front l mower unit to the main frame `for translatory sub-frame 200 is connected* to, the frame, are all preferably made with a rubber liner between the socket and the ball of the joint. In order to achieve this construction, the joint is composed of two halves 302 and 303 (see the front ball and socket joint cf link 5|, Figure` 4), which are bolted together by means of a cap screw 304 joining the front ends of the socket and a through bolt 306 which clamps together the back ends of the socket, and at the same time clamp-s the socket to the link.` The haliportionv of the ball and Asocket joint, illustrated at234 in Figure 9, is shown as having a lining 301, which is preferably made of natural or synthetic rubber. The

movement in a vertical plane and for tipping movement about an axis longitudinally of the frame, a sub-frame, means mounting the subframe to the main frame for translatory movement in a vertical plane and for tipping movement about an axis longitudinally of the frame, and means pvotally connecting each of the wing mowers to the sub-frame for swinging movement in a transverse vertical plane.

5. A power mower, comprising a main frame, wing mower units extending sideways. from said frame, means mounting said mower for translatcry movement in a vertcal plane and for rocking movement about an axis longitudinally of the frame, adjustable yieldable means r`for transferring a portion of the mower weight to the main frame, the transfer of weight being substantially lconstant throughout a plurality of a rigid vertical' pivotv member secured to the, longitudinal member, a

transport.

translatory movement in a vertical planeand for rocking movement about an axis longitudi-v nally of themain frame, adjustable yieldable means for constantly transferring to the main frame all of the sub-frame and wing mower weight save that necessary to maintain the proper contact of the wing mowers with the ground.

7. A power mower, a main frame, a mower unit infront of the 'fra-me, connections means pivotally connecting the mower unit and main frame', including'a three-point pivotal connection on the mower, and a four-point pivotal connection on the frame.

8. A power mower, comprising a main frame, a sub-frame, a pair of wing mowers pivotally vconnected to the sub-frame along axes longitudinally of the main frame, and means connecting the sub-frame to the main frame .including an arm pivoted on the main frame for movement in V 2,299,859 mower positions' relative to the frame, saidv thereon journaled on the sub-frame along an axis vnormally transverse to the main frame, driv- 'ing means connecting the power unit and the counter-shaft, a wing mower, a pulley mounted von the wing mower, an endless belt 'connecting the pulley of the sub-frame andthe pulley'of the wing mower, means pivotally mountingA the wing mower for swinging movement with respect 'to the sub-frame, said pivotal axis being tangent said drive shaft, a mower having rotating reels mounting the mower units for swinging movea vertical plane, said arm being: universally connected to the sub-frame, and means for holding the sub-frame from pivotally moving about a transverse axis.

9. A power mower, comprising a main frame, a sub-frame, a pair oi wing mowers pivotally conected to the sub-frame along axes longitudinally of the main frame, and means connecting the sub-frame to themain frame including an arm pivoted on the main frame for movement in a vertical plane, said arm being universally connected to the sub-frame, and means for holding the subframe from pivotally moving about a vertical axis.

10. In a lawn mower, a drive pulley, a driven pulley, a driving connection comprising an endless belt which rides on both pulleys, means mounting the pulleys for relative swinging movement of the planes of the pulleys about a line substantially tangent to the pitch lines of the y pulleys on the tight belt side of one pulley and the loose belt side of the other pulley.

11. A lawn mower, a frame, a drive pulley mounted for rotation in a plane n xed with respect to the frame, a mower unit, a driven pulley mounted for rotation in a plane fixed with respect to the mower unit, an endless belt mounted for running on the pulleys, means pivotally mounting the mower unit for swinging movement with respect to the frame, the pivotal axis of said mounting means being tangent to approxihaving a power unit thereon, a sub-frame, means` mounting the sub-frame 4on themain frame for translatory movement in a vertical plane and 'for rocking movementvabout an axis longitudinally of the frame, a counter-shaft vhaving a pulley ment in vertical planes, the axis of swinging of each mower being through the pitch line of the pulley of that mower on one side of the belt and through the pitch line of the corresponding pul-y ley of the drive shaft on the other side of thev belt.

v 15. A mowing machine, comprising a frame, a mowing unit carried thereby, a pivot journal and an extending pivot shaft for insertion in the Journal,` both having their pivot axes longitudinallyaligned parallel with the frame, one being upon theframe and the other on the mowing unit, whereby the-mowingunit may be readily attached to the vframe by insertion of the pivot shaft endwise in the pivot journal.

16. A device of the type described in claim 15 characterized bythe fact that the shaft includes a shoulder, and there is a manually moveable clip engageable with the shoulder for holding the shaft against longitudinal movement.

17. A device of the type set forth in claim 15 characterized by the fact thatboth the frame and mowing units include pulleys having a power transmitting -belt thereover and by the fact that the shaftis endwise 4adjustable to vary the belt tension.

18. A power mower, including a main frame, a sub-frame, a pair of wing mowers mounted on the sub-frame and normally extendinglaterally therefrom, said wing mowers being pivoted to the sub-frame for swinging movement to a vertical position, and means on the frame releasably holding the mowers in said vertical position.

19. A power mower comprising a main frame with a power supplying shaft journaled thereon, a plurality of cutter operating shafts generally parallel to said power supplying shaft, a support for one of said cutter operating `shafts fioatingly engaged to the main frame, wheels on said three shafts located in alignment, and flexible strands of transmitting means engaged thereon, the rotation of said means being such that tension in one strand from said power supplying shaft operates the iloatingly supported shaft and tension in another strand from the floating shaft operates the third shaft, `and link means for oatingly engaging said support to said frame extending in the direction of the resultant of the tensions in said two strands.

20'. A power mower; a frame, a mower unit in spaced relation with the frame, link means pivotally connecting the mower to the frame for translatory movement in a vertical plane and for movement about an axis longitudinally of the frame, other link means pivoted Ato the frame and to the mower for tilting the mower upwardly about an axis transverse of the frame when the mower rocks vertically above and below a normal horizontal plane with respectl to the frame.

211. A power mower, comprising a frame, a power supplying shaft rotatably mounted on the frame, a mower unit having a rotating reel and reel shaft arranged so as to be normally generally parallel with said power supplying shaft, pulleys on the power shaft and reel shaft, power transmitting belt means tensloned over said pulleys, stay link means extending from the frame to the mower unit `for maintaining them in spaced relation, said link means being in arrangement so that the direction of forces thereby transmitted are substantially parallel to the resultant of the belt tension forces.

22. A power lawn mower, comprising a tractor structure and a cutter structure with independent ground contacts, three universal pivots displaced laterally and vertically on one of said structures, a transverse axis on the other of said structures horizontally displaced from one of said pivots, a swing frame pivoted on said axis and connected to the said one ofthe universal pivots, fourth and fifth vuniversal pivots on the structure. that supports said axis and displaced in the direction of travel from the other two of said three pivots, and links disposed generally in the direction of travel connecting the respectively aligned pivots on saidtractorstructure and cutter structure.

23. In a power lawn mower, a tractorr unit means adapted to constrain said cutter structure Y i to move in a substantially vertical plane, whereby` said universal connection prevents lateral movements of said cutter structure relatively to said tractor.

24,'In a power lawn mower, a tractor unit comprising ground supported rolling member, a

-frame carried thereby, and a motor thereon connected to operate said rolling member, a cutter structure with ground contact disposed transversely to the direction of travel and floatingly connected to said tractor, said floating connection comprising a swing frame pivoted to the tractor on a transversely disposed axis and universally connected to the cutter structure at a point horizontally displaced from said axis, and means including plural pivots disposed on a transverse axis of said cutter structure vertically displaced from said universal connection,

other -pivots `on the tractor and horizontally` displaced from the first said pivots and from the axis thereof, andv universally connected links disposed in the direction of travel conneeting the respective pivots on said cutter structure and on said tractor.

RALPH W. SPEISER. 

